HomeMy WebLinkAboutWPO201900057 Correspondence 2020-02-28PROJECT MANAGEMENT
SHIMCIVIL ENGINEERING
LAND PLANNING
ENGINEERING'
February 28, 2020
Emily Cox
County Engineering
Albemarle County Community Development
WPO 201900057 Proffit Rd Townhomes North — Comment Response for Resubmittal 3
Dear Emily,
Thank you for your review of the VSMP Plan for Proffit Rd Townhomes North. We have revised the
design of the VSMP Plan since your plan approval issued on Feb. 5, 2020.
The plan has been revised in one way: we have replaced the 120" CMP detention system with an ADS Stormtech
BMP. As the attached plans and calculations will show, this BMP still meets the energy balance equation. The
main difference in the switch is that the BMP provides 40% nutrient removal, so the required nutrient credit
purchase is reduced to 2.45 lbs.
Detailed summary of changes:
1. Pipes A2-Al, B2-B1, C2-C1 slightly revised per BMP change
-updated LD 229
-updated profiles
2. BMP details updated
-added installation sheets and details from ADS to plans and SWM calc packet
-added maintenance schedule to plans
3. Grading above BMP slightly revised to meet manufacturer specs
4. HydroCAD & Energy Balance Equation updated
5. VRRM spreadsheet
-updated plans and calc packet referencing treatment and nutrient credit purchase amount.
Attached you will find a copy of the updated Plans, SWM Cale packet, SWPPP, and WPO Application.
Additionally, in response to your email on 2/5/20, we have attached a bond calculation spreadsheet and a
Registration Statement showing the correct operator (Albemarle Land Development LLC). We will await for
county approval before requesting the pre -con, purchasing nutrient credits, and paying the DEQ permit portion.
If you have any questions or concerns about these revisions please feel free to email me at keane@shimp-
engineering com and copy Justin Shimp at justin@shimp-en in�g com or call at (434) 299-9843 and we can
discuss in further detail.
Best Regards,
Keane Rucker, E.I.T.
Shimp Engineering, P.C.